White matter microstructure among perinatally HIV-infected youth: a diffusion tensor imaging study.

We evaluated white matter microstructure integrity in perinatally HIV-infected (PHIV) youths receiving cART compared to age- and gender-matched healthy youths through DTI metrics using voxel-based morphometry (VBM). We investigated 14 perinatally HIV-infected patients (age 17.9 ± 2.5 years) on cART and 17 healthy youths (HC) (age 18.0 ± 3.0 years) using a 3T MRI scanner. Four DTI-derived metrics were fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). Statistical analysis was done with voxel-based analysis of covariance (ANCOVA), with age and gender as covariates. Region-of-interest secondary analyses in statistically significant regions were also performed. Regional increases in FA in the PHIV youths were found in left middle frontal gyrus, right precuneus, right lingual gyrus, and left supramarginal gyrus. Increased MD was found in the right precentral gyrus while decreased MD was found in the white matter of the right superior parietal lobule and right inferior temporal gyrus/fusiform gyrus. Regions of increased/decreased RD overlapped with regions of increased/decreased MD. Both increased and decreased AD were found in three to four regions respectively. The regional FA, MD, RD, and AD values were consistent with the voxel-based analysis findings. The findings are mostly consistent with previous literature, but increased FA has not been previously reported for perinatally HIV-infected youths. Potentially early and prolonged therapy in our population may have contributed to this new finding. Both toxicity of antiretroviral therapy and indolent infection must be considered as causative factors in the DTI metric changes that we have observed.

Feasibility of endovascular repair of ascending aortic pathologies as part of an FDA-approved physician-sponsored investigational device exemption.

OBJECTIVE: Endovascular treatment of ascending aortic lesions has been reported, but to date, no FDA-approved studies have been conducted to define feasibility and the use of endografts in this particular location or to analyze the critical factors involved. METHODS: Patients were consented for entry into an FDA-approved physician-sponsored investigational device exemption study to investigate the outcome of those with ascending aortic pathologies. These patients were suitable according to the instructions for use for endovascular repair with a Valiant Captivia (Medtronic, Inc, Minneapolis, Minn) thoracic stent graft, a device designed specifically for deployment in the ascending aorta. All patients had sequential gated-cardiac computed tomography scans, with data being entered into the VQI Complex TEVAR software (West Lebanon, NH). All procedures were performed in a hybrid room, with the capability to convert to an open repair to ensure maximal patient protection. The first five patients constituted the feasibility study, with continued enrollment based on initial results and submission of an annual report to the FDA. RESULTS: Thirty-nine patients were screened, and six patients were entered into the physician-sponsored investigational device exemption study. Although there was no early mortality, there was one late death. All patients had sequential computed tomographies and cardiac echocardiograms with no evidence of migration, one type 1a endoleak, one postoperative stroke, and regression of the aortic lesions in the excluded aortic segment. CONCLUSIONS: In this feasibility study, the preliminary evaluation of endovascular treatment for ascending aortic pathologies demonstrates uniform accuracy of deployment and secure fixation up to 17.5 months of follow-up. There is positive remodeling of the excluded aortic segments similar to surveillance studies involving the descending aorta.

Comparison of Neurocognitive Outcomes after Carotid Endarterectomy and Carotid Artery Stenting.

Cognitive and emotional outcomes after carotid endarterectomy (CEA) and carotid artery stenting with embolic protection device (CAS + EPD) are not clear. Patients were entered prospectively into a United States Food and Drug Administration-approved single-center physician-sponsored investigational device exemption between 2004 and 2010 and received either CEA or CAS + EPD. Patients underwent cognitive testing preprocedure and at 6, 12, and 60 months postprocedure. Cognitive domains assessed included attention, memory, executive, motor function, visual spatial functioning, language, and processing speed. Beck Depression and anxiety scales were also compared. There were a total of 38 patients that met conventional indications for carotid surgery (symptomatic with ≥50% stenosis or asymptomatic with ≥70% stenosis)-12 patients underwent CEA, whereas 26 patients underwent CAS + EPD. Both CEA and CAS + EPD patients showed postprocedure improvement in memory and executive function. No differences were seen at follow-up in regards to emotional dysfunction (depression and anxiety), attention, visual spatial functioning, language, motor function, and processing speed. Only two patients underwent neuropsychiatric testing at 60 months-these CAS + EPD patients showed sustained improvement in memory, visual spatial, and executive functions. In conclusion, cognitive and emotional outcomes were similar between CEA and CAS + EPD patients.

Intravascular ultrasound.

Intravascular ultrasound (IVUS) has an interesting history that parallels that of many of the advancements that have led to the endovascular era. The use of IVUS in conjunction with standard cross-sectional imaging and three-dimensional reconstructions offers a powerful tool in both the diagnosis and treatment of complex vascular pathology. The use of IVUS has increased over the years and is currently in the process of being incorporated into several modalities that will offer more in the way of real-time information in both the aortic arena and the treatment of increasingly complex peripheral vascular disease. Currently, we use IVUS as a powerful adjunct in combination with other modalities to increase our understanding of vessel architecture and assist in the management of complex vascular pathology.

Patient outcomes and thoracic aortic volume and morphologic changes following thoracic endovascular aortic repair in patients with complicated chronic type B aortic dissection.

OBJECTIVE: True and false lumen changes and patient outcomes following thoracic endovascular aortic repair (TEVAR) for patients with stable type B dissection have been described by the The Investigation of Stent Grafts in Aortic Dissection (INSTEAD) trial. However, these changes have not been described in TEVAR patients treated for complications of chronic dissection. METHODS: A single-institution study was conducted of 73 prospectively evaluated patients treated for complications of chronic type B dissection from 2002 to 2010. Spiral computed tomography reconstructions using M2S (Medical Media Systems, West Lebanon, NH) were analyzed for sequential changes in aortic volume and diameter during patient follow-up. Changes in aortic volume and diameter were tabulated as a percent change from preoperative values. Patient outcomes were determined by sequential evaluations postprocedure. RESULTS: TEVAR was successfully performed in 72 out of the 73 patients (99%). Indications for intervention were aortic enlargement (n = 62), failure of medical management (n = 7), and perforation (n = 4). The 30-day all-cause mortality rate was 14%; events were due to retrograde dissection (n = 4), cardiac-related (n = 4), and rupture (n = 2). Eleven out of the 72 patients (15%) required a secondary procedure for endoleak (n = 7) and persistent distal perfusion of the false lumen (n = 4). Mean percentage expansion of the thoracic true lumen was noted during the follow-up period: 38%, 46%, 71%, and 114% at 1-, 3-, 6-, and 12-month follow-up, respectively. Concomitant regression of the thoracic false lumen of -65%, -68%, -84%, and -84% was observed at the same intervals, respectively. Patients with an initial extension of the thoracic dissection into the infrarenal aorta (n = 46) had an increase in mean percentage change of aortic diameter and volume to 21% and 17% at 1 year, respectively. By contrast, in the patient group without infrarenal dissection (n = 14), the infrarenal aortic diameter and volume remained relatively unchanged at 3% and -0.9%, respectively, at 1-year postintervention. CONCLUSIONS: TEVAR is a potential treatment option for patients experiencing complications of chronic type B dissection. During follow-up, there is a predictable expansion of the thoracic true lumen and regression of the thoracic false lumen. These findings correlate with those of the INSTEAD trial, which demonstrated false lumen regression and true lumen expansion in a cohort of patients with stable type B dissection. However, many patients with extension of thoracic dissection into the infrarenal aorta demonstrate continued aortic dilation and, on occasion, the need for secondary intervention for persistent distal perfusion. Further analysis is needed in this subgroup of patients so as to better determine potential predictors and the clinical significance of post-TEVAR infrarenal expansion. Moreover, further investigations may support a role for secondary endovascular intervention in remedying persistent infrarenal aortic expansion after TEVAR for chronic dissection.

Distribution of intimomedial tears in patients with type B aortic dissection.

OBJECTIVE: Thoracic endovascular aortic repair is a promising means of treating patients with complicated type B aortic dissection by excluding the intimomedial tears. This study aims to characterize the location of tears and to propose a classification of type B aortic dissections based on these findings. METHODS: Advanced protocols in computed tomography scans of patients with type B aortic dissection were used to identify the size and location of intimomedial tears in relation to the origin of the left subclavian artery. Aortic imaging details in 72 un-operated patients were used as a reference standard. From 1999 to 2005, 44 patients underwent primary endovascular treatment for complications of type B aortic dissection. RESULTS: Each patient had an average of 2.8 +/- 2.11 intimomedial tears. The median intimomedial tear surface area was 0.63 cm(2). The presence of >or=3 or >or=5 intimomedial tears in the descending thoracic aorta did not correlate with aortic branch malperfusion (P > .05). Thirteen of 26 (50%) patients with a tear >1.9 cm(2) had aortic branch malperfusion (P = .032). Ten of 14 (71%) patients with a tear >4.86 cm(2) (mean plus one standard deviation) had aortic branch malperfusion (P = .002). The location of tears ranged from -6 mm to +459.2 mm from the left subclavian artery orifice: 80.5% (n = 99) of these tears were above the reference origin of the celiac artery. Eight of 13 patients (62%) with a tear distal to 282 mm (the orifice of the celiac artery) had aortic branch malperfusion in (P = .04). A classification for the location of intimomedial tears is proposed with potential clinical relevance to endovascular repair: type 1 has no identifiable tears; type 2 has one or more tears with no tears distal to the orifice of the celiac artery; type 3 has tears involving the branch vessels of the abdominal aorta; and type 4 has intimomedial tears distal to the aortic bifurcation. CONCLUSIONS: Characterization and location of intimomedial tears using computed tomography (CT) imaging is feasible and represents an important step in the management of type B aortic dissection. The location and surface area of tears is associated with malperfusion. Based on the proposed classification and anatomic reference data, three out of every four patients may have a favorable constellation of intimomedial tears (type 1 or 2) that would be amenable to endovascular repair and reverse aortic remodeling. The clinical correlation will be established in upcoming studies.

Midterm results of endovascular treatment of complicated acute type B aortic dissection.

OBJECTIVES: The operative mortality and morbidity of patients with complicated acute type B aortic dissection remain high. The endovascular approach has been proposed as a potential alternative. The purpose of this study is to review the contemporary outcome of patients undergoing endovascular treatment for complicated acute type B aortic dissection. METHODS: A retrospective analysis of 28 patients undergoing endovascular interventions for acute type B aortic dissection was performed. Kaplan-Meier survival analysis was used for statistical computation. RESULTS: Indications for emergency endografting were rupture in 4 (14%) patients, severe lower body malperfusion in 8 (29%) patients, visceral/renal malperfusion in 7 (25%) patients, persistent chest pain despite proper anti-impulsive therapy in 5 (18%) patients, uncontrollable hypertension in 1 (4%) patient, and acute dilatation of false lumen with impending rupture in 3 (11%) patients. Three (11%) patients died early. Three patients died during follow-up of non-aorta-related causes. Overall survival was 82% and 78% at 1 and 5 years' follow-up, respectively. The aorta-related mortality was 10% for the entire follow-up period. Complete thrombosis of the false lumen in the thoracic aorta was achieved in 22 (85%) members of the surviving cohort, and partial thrombosis was achieved in the remainder. The rate of treatment failure according to Stanford criteria was 18% at 5 years. Mean follow-up was 36 months, and follow-up was complete in 28 (100%) patients. CONCLUSIONS: Thoracic aortic endografting for complicated acute type B aortic dissection can be performed with a relatively low postoperative morbidity and mortality in experienced hands. The endovascular approach to life-threatening complications of acute type B aortic dissection appears to have a favorable outcome in midterm follow-up.

Risk factors for early and late mortality after thoracic endovascular aortic repair.

OBJECTIVE: The risk factors associated with death after thoracic endovascular aortic repair are poorly understood. The aim of this study is to analyze the risk factors associated with early and late mortality after thoracic endovascular aortic repair. METHODS: A total of 153 patients underwent 184 thoracic endovascular aortic repairs between 1998 and 2005. Prospectively collected data were entered into statistical software. Univariate and multivariate analyses were performed. RESULTS: The underlying pathologies included descending thoracic aortic aneurysm (n = 91), acute type B aortic dissection (n = 25), chronic type B aortic dissection (n = 42), aortic transection (n = 12), and penetrating aortic ulcer (n = 14). Thoracic endovascular aortic repair was technically successful in all but 3 patients. Another 3 patients required an open repair within the first month. Early and late mortality rates were 9.8% (n = 18) and 19% (n = 35) in a 16-month average period of follow-up, respectively. Type I procedural endoleak was the only significant predictor of early death in the multivariate model (P = .0036; odds ratio: 8.4; 95% confidence interval: 1.6-43.9). Multivariate Cox regression revealed chronic obstructive pulmonary disease (P = .024; odds ratio: 3.8; 95% confidence interval: 1.2-12.1), postoperative myocardial infarction (P = .0053; odds ratio: 9.7; 95% confidence interval: 2.0-48.4), and acute renal failure (P = .0006; odds ratio: 22.8; 95% confidence interval: 3.8-137.6) to be independent risk factors for late mortality. CONCLUSION: Procedural type I endoleak is an independent risk factor of early mortality after thoracic endovascular aortic repair. Chronic obstructive pulmonary disease, postoperative myocardial infarction, and acute renal failure are predictors of late death in the multivariate analysis.

Increased anterior cingulate/medial prefrontal cortical glutamate and creatine in bipolar depression.

Proton magnetic resonance spectroscopy ((1)HMRS) is an in vivo brain imaging method that can be used to investigate psychotropic drug mechanism of action. This study evaluated baseline (1)HMRS spectra of bipolar depressed patients and whether the level of cerebral metabolites changed after an open trial of lamotrigine, an anti-glutamatergic mood stabilizer. Twenty-three bipolar depressed and 12 control subjects underwent a MRS scan of the anterior cingulate/medial prefrontal cortex. The scan was performed on a GE whole-body 1.5 T MRI scanner using single-voxel PRESS (TE/TR=30/3000 ms, 3 x 3 x 3 cm(3) and post-processed offline with LCModel. Baseline CSF-corrected absolute concentrations of glutamate+glutamine ([Glx]), glutamate ([Glu]), and creatine+phosphocreatine ([Cr]) were significantly higher in bipolar depressed subjects vs healthy controls. The non-melancholic subtype had significantly higher baseline [Glx] and [Glu] levels than the melancholic subtype. Remission with lamotrigine was associated with significantly lower post-treatment glutamine ([Gln]) in comparison to non-remission. These data suggest that non-melancholic bipolar depression is characterized by increased glutamate coupled with increased energy expenditure. Lamotrigine appears to reduce glutamine levels associated with treatment remission. Further study is encouraged to determine if these MR spectroscopic markers can delineate drug mechanism of action and subsequent treatment response.

Risk factors of neurologic deficit after thoracic aortic endografting.

BACKGROUND: Stroke and spinal cord injury (SCI) remain the most devastating complications of thoracic endovascular aortic repair (TEVAR). The risk factors associated with these complications are poorly understood. The aim of this study was to analyze the risk factors associated with neurologic deficits after TEVAR. METHODS: From 1998 to 2005, 153 patients underwent 184 TEVARs. Computed tomography scans, angiograms, and medical records were reviewed. TEVAR was completed in all but 3 patients. The underlying pathologies included descending thoracic aortic aneurysm in 91, acute type B aortic dissection in 25, chronic type B aortic dissection in 42, aortic transection in 12, and penetrating aortic ulcer in 14. RESULTS: Stroke developed in 8 patients, and SCI developed in another 8 patients (4 immediate, 4 delayed paraplegia/paraparesis). The procedure-associated stroke and SCI rate was 4.3% (8/184). Univariate statistical analysis revealed increased postoperative stroke with obesity, significant intraoperative blood loss, and evidence of peripheral vascular embolization/thrombosis. Aneurysmal pathology, iliac conduit, and hypogastric artery coverage were highly associated with postoperative SCI after TEVAR. Early and late mortality were 9.8% (n = 18) and 19% (n = 35) in a 16-month average period of follow-up. CONCLUSIONS: The incidence of stroke and SCI after TEVAR was 4.3% (8/184). The risk factors associated with postoperative stroke were obesity, intraoperative blood loss, and vascular embolization. Aneurysm as an underlying pathology, the use of an iliac conduit, and coverage of the hypogastric artery were all associated with SCI. These risk factors for SCI may be markers of tenuous collateral blood supply to the spinal cord.

A follow-up study of MPS I patients treated with laronidase enzyme replacement therapy for 6 years.

Recombinant human alpha-L-iduronidase (Aldurazyme, laronidase) was approved as an enzyme replacement therapy for patients with the lysosomal storage disorder, mucopolysaccharidosis I (MPS I). In order to assess the long-term safety and efficacy of laronidase therapy, 5 of 10 patients in the original laronidase Phase 1/2 clinical trial were re-evaluated after 6 years of treatment. Lysosomal storage was further improved at 6 years (urinary glycosaminoglycans (GAG) excretion decreased 76%; mean liver size at 1.84% of body weight). Shoulder maximum range of motion was maintained or further increased and reached a mean 33.2 (R) and 25.0 (L) degrees gained in flexion and 34.0 (R) and 27.3 (L) degrees gained in extension. Sleep apnea was decreased in four of five patients and the airway size index improved. Cardiac disease evaluations showed no progression to heart failure or cor pulmonale but pre-existing significant valve disease did progress in some patients. Substantial growth was observed for the pre-pubertal patients, with a gain of 33 cm (27%) in height and a gain of 31 kg in weight (105%). In general, the evaluated patients reported an improved ability to perform normal activities of daily living. Overall these data represent the first evidence that laronidase can stabilize or reverse many aspects of MPS I disease during long-term therapy and that early treatment prior to the development of substantial cardiac and skeletal disease may lead to better outcomes.

The role of aortic neck dilation and elongation in the etiology of stent graft migration after endovascular abdominal aortic aneurysm repair with a passive fixation device.

OBJECTIVE: Endovascular repair of abdominal aortic aneurysm (AAA) is complicated by the potential for stent graft migration over time. Factors including the type of fixation, initial proximal fixation length, and dilation and elongation of the infrarenal aortic neck may contribute to device migration. We sought to determine when device migration is a real phenomenon with actual device movement that compromises aneurysm exclusion. METHODS: Computed tomographic (CT) scans and computer reconstructions of all patients undergoing endovascular AAA repair with a passive fixation device at our institution from June 1996 to October 2004 were retrospectively reviewed. The distance from the distal renal artery to the proximal end of the stent graft at the time of initial deployment was determined for each patient. Migration was defined as a distance increase greater than 5 mm in the follow-up period; proximal fixation length, aortic neck enlargement and elongation, and neck angle were then measured. Data were further analyzed with respect to AAA growth, development of endoleak, AAA rupture, and the need for reintervention. RESULTS: A total of 308 patients with endovascular AAA repairs using a passive fixation device had complete postoperative imaging data sets; 48 patients (15.6%) with stent graft migration of 5 mm or more were identified, and 25 (8.1%) of these had a migration of 10 mm or more. Seventeen (35.4%) of 48 migration patients had a total loss of the proximal seal zone (loss patients); their average migration distance was 17.7 +/- 12.0 mm, with a mean neck shortening of 13.6 +/- 14.2 mm, and the average proximal fixation length loss was 14.0 +/- 7.6 mm. Those 31 patients with an intact proximal seal zone (nonloss patients) showed an average migration of 9.4 +/- 3.7 mm, with a mean neck lengthening of 9.6 +/- 8.4 mm and an average proximal fixation length change of 0.7 +/- 8.0 mm. Univariate analysis demonstrated significant differences between the loss and nonloss patients in follow-up duration (65.9 +/- 20.4 months vs 45.9 +/- 26.4 months; P = .01), neck dilatation at the distal renal artery (4.6 +/- 4.5 mm vs 1.8 +/- 1.9 mm; P = .026), stent graft migration distance (17.7 +/- 12.0 mm vs 9.4 +/- 3.7 mm; P = .001), change in aortic neck length (-13.6 +/- 14.2 mm vs 9.6 +/- 8.4 mm; P < .0001), change in proximal fixation length (-14.0 +/- 7.6 mm vs 0.7 +/- 8.0 mm; P < .0001), change in AAA size (1.8 +/- 7.1 mm vs -3.6 +/- 9.7 mm; P = .033), and use of a stiff body stent graft (47.1% vs 19.4%; P = .043). However, only change in aortic neck length was statistically significant on multivariate analysis (odds ratio, 0.75; 95% confidence interval, 0.591-0.961; P = .022). There were no differences between the loss and nonloss patients in time to migration discovery, initial AAA size, initial aortic neck diameter or length, initial device oversizing, initial neck angle, neck angle increase, type II endoleak, or AAA rupture. Eight of the 17 loss patients have been treated with proximal aortic cuffs; the remainder have refused reintervention, died of unrelated causes, or elected to have open repair. CONCLUSIONS: Postoperative elongation of the infrarenal aortic neck may create the radiographic perception of migration without necessarily causing a loss of proximal stent graft fixation. Patients with a total loss of the proximal seal zone actually have infrarenal aortic neck shortening, with a degree of neck dilatation beyond initial device oversizing that may compromise proximal fixation length. Conversely, those with an intact proximal seal zone demonstrate aortic neck elongation equivalent to migration, with no loss of proximal fixation length; these patients have a benign natural history without intervention. Thus, aortic neck dilatation beyond oversizing, aortic neck shortening, and loss of proximal fixation length are more clinically relevant predictors of proximal stent graft failure than simple migration distance.

Endograft exclusion of acute and chronic descending thoracic aortic dissections.

OBJECTIVES: To analyze the results of endograft exclusion of acute and chronic descending thoracic aortic dissections (Stanford type B) with the AneuRx (n = 5) and Talent (n = 37) thoracic devices and to compare postoperative outcomes of endograft placement acutely (<2 weeks) and for chronic interventions. METHODS: Patients treated for acute or chronic thoracic aortic dissections (Stanford type B) with endografts were included in this study. All patients (n = 42) were enrolled in investigational device exemption protocols from August 1999 to March 2005. Three-dimensional computed tomography reconstructions were analyzed for quantitative volume regression of the false lumen and changes in the true lumen over time (complete >95%, partial >30%). RESULTS: Forty-two patients, all of whom had American Society of Anesthesiologists (ASA) risk stratification > or =III and 71% with ASA > or = IV, were treated for Stanford type B dissections (acute = 25, chronic = 17), with 42 primary and 18 secondary procedures. All proximal entry sites were identified intraoperatively by intravascular ultrasound (IVUS). The procedural stroke rate was 6.7% (4/60), with three posterior circulation strokes. Procedural mortality was 6.7% (4/60). The left subclavian artery was occluded in 11 patients (26%) with no complaints of arm ischemia, but there was an association with posterior circulation strokes (2/11) (18%). No postoperative paraplegia was observed after primary or secondary intervention. Complete thrombosis of the false lumen at the level of endograft coverage occurred in 25 (61%) of 41 patients < or =1 month and 15 (88%) of 17 patients at 12 months. Volume regression of the false lumen was 66.4% (acute) and 91.9% (chronic) at 6 months. Lack of true lumen volume (contrast) increase and increasing false lumen volume (contrast) suggests continued false lumen pressurization and the need for secondary reintervention. Thirteen patients (31%) required 18 secondary interventions for proximal endoleaks in 6, junctional leaks in 3, continued perfusion of the false lumen from distal re-entry sites in 3, and surgical conversion in 4 for retrograde dissection. CONCLUSIONS: Preliminary experience with endografts to treat acute and chronic dissections is associated with a reduced risk of paraplegia and lower mortality compared with open surgical treatment, the results of medical treatment alone, or a combination.

Smaller subcortical volumes and cognitive deficits in children with prenatal methamphetamine exposure.

The purpose of this pilot study was to examine possible neurotoxic effects of prenatal methamphetamine (Meth) exposure on the developing brain and on cognition. Meth-exposed children (n=13) and unexposed control subjects (n=15) were evaluated with MRI. Global brain volumes and regional brain structures were quantified. Ten Meth-exposed and nine unexposed children also completed neurocognitive assessments. Meth-exposed children scored lower on measures of visual motor integration, attention, verbal memory and long-term spatial memory. There were no differences among the groups in motor skills, short delay spatial memory or measures of non-verbal intelligence. Despite comparable whole brain volumes in each group, the Meth-exposed children had smaller putamen bilaterally (-17.7%), smaller globus pallidus (left: -27%, right: 30%), smaller hippocampus volumes (left: -19%, right: -20%) and a trend for a smaller caudate bilaterally (-13%). The reduction in these brain structures correlated with poorer performance on sustained attention and delayed verbal memory. No group differences in volumes were noted in the thalamus, midbrain or the cerebellum. In summary, compared with the control group, children exposed to Meth prenatally exhibit smaller subcortical volumes and associated neurocognitive deficits. These preliminary findings suggest prenatal Meth exposure may be neurotoxic to the developing brain.

Complications of endovascular repair of high-risk and emergent descending thoracic aortic aneurysms and dissections.

PURPOSE: The advent of endovascular prostheses to treat descending thoracic aortic lesions offers an alternative approach in patients who are poor candidates for surgery. The development of this approach includes complications that are common to the endovascular treatment of abdominal aortic aneurysms and some that are unique to thoracic endografting. METHODS: We conducted a retrospective review of 60 emergent and high-risk patients with thoracic aortic aneurysms (TAAs) and dissections treated with endovascular prostheses over 4 years under existing investigational protocols or on an emergent compassionate use basis. RESULTS: Fifty-nine of the 60 patients received treatment, with one access failure. Thirty-five patients received treatment of TAAs. Four of these procedures were performed emergently because of active hemorrhage. Twenty-four patients with aortic dissections (16 acute, 8 chronic) also received treatment. Eight of the patients with acute dissection had active hemorrhage at the time of treatment. Three devices were used: AneuRx (Medtronic; n = 31), Talent (Medtronic; n = 27), and Excluder (Gore; n = 1). Nineteen secondary endovascular procedures were performed in 14 patients. Most were secondary to endoleak (14 of 19), most commonly caused by modular separation of overlapping devices (n = 8). Other endoleaks included 4 proximal or distal type I leaks and 2 undefined endoleaks. The remaining secondary procedures were performed to treat recurrent dissection (n = 1), pseudoaneurysm enlargement (n = 3), and endovascular abdominal aortic aneurysm repair (n = 1). One patient underwent surgical repair of a retrograde ascending aortic dissection after endograft placement. Procedure-related mortality was 17% in the TAA group and 13% in the dissection group, including 2 acute retrograde dissections that resulted in death from cardiac tamponade. Overall mortality was 28% at 2-year follow-up. CONCLUSION: Although significant morbidity and mortality remain, endovascular repair of descending TAAs and dissections in patients at high-risk patients can be accomplished with acceptable outcomes compared with traditional open repair. The major cause for repeat intervention in these patients was endoleak, most commonly caused by device separation. Improved understanding of these complications may result in a decrease in secondary procedures, morbidity, and mortality in these patients. The need for secondary interventions in a significant number of patients underscores the necessity for continued surveillance.

Endovascular abdominal aortic aneurysm repair using the AneuRx stent graft: impact of excluding accessory renal arteries.

The aim of this study was to evaluate clinical sequelae of accessory renal artery exclusion during endo-AAA repair. Medical records and pre- and postoperative CT scans were reviewed from 114 AAA patients treated with the AneuRx stent graft between 1996-2001. Thirty-seven accessory renal arteries were identified in 32/114 patients (28%) with 19/32 patients having infrarenally located accessory renal arteries. In group I (11 patients), the stent graft excluded 11 accessory renal arteries. In group II (8 patients), eight accessory renal arteries were not excluded. Average infrarenal neck length was 24.9 mm in group I vs. 30.7 mm in group II (p = 0.07). The average length of device seal was similar in both groups (19.4 vs. 18.5 mm, p = 0.67). There were no perioperative deaths, significant postoperative hypertension, rise in serum creatinine, or postoperative renal infarctions in either group. Three of eight patients (38%) in the non-excluded group developed type I proximal endoleaks whereas none in the excluded patient group did (p = 0.06). Accessory renal arteries may be safely excluded during endovascular AAA repair and may result in a more secure proximal device fixation.

Late-onset type II endoleaks and the incidence of secondary intervention.

Type II endoleaks are a recognized complication of endoluminal treatment of abdominal aortic aneurysms. In order to better understand the natural history of type II endoleaks and their influence on secondary procedures, we examined our experience with patients who developed isolated type II endoleaks 6 months or more after their original procedure. We conducted a retrospective review of patients who underwent endoluminal repair of infrarenal abdominal aortic aneurysms with bifurcated endoluminal devices at a single institution from June 1996 to June 2000. Endoleak surveillance was performed on all patients by using a defined CT angiogram protocol. Patients with definitive and isolated type II endoleaks on CT angiogram were identified. Patients with indeterminate endoleaks or a combination of different types of endoleaks were excluded. Data were analyzed on the basis of early (<6 months) or late occurrence of isolated type II endoleak. Fifty patients were identified with isolated type II endoleaks. Of these patients, 20 (40%) had endoleaks discovered before the 6-month follow-up interval whereas the majority (60%) had new type II leaks discovered at least 6 months after their initial procedure. The timing of endoleak occurrence did not significantly influence the rate of spontaneous endoleak resolution between the early- (<6 months) and late-onset (>6 months) groups, which was nearly identical (40% vs. 43%). Ten patients in the early group and seven of the late-onset group required secondary intervention for treatment of type II endoleak (50% vs. 23%; NS). Three patients in the early group underwent surgical conversion (vs. 0 patients in the late-onset group). The mortality rate was not significantly different between groups (15% vs. 7%). Most isolated type II endoleaks in this patient population occurred 6 months or more after initial endoluminal repair of infrarenal abdominal aortic aneurysm. Timing of type II endoleak occurrence did not significantly affect the rates of spontaneous resolution or mortality. Although differences were observed in the number of patients receiving secondary interventions, these findings did not reach statistical difference. All patients who required surgical conversion had early type II endoleaks. There were no observed ruptures in patients with increased aneurysm size treated with secondary intervention or those with stable aneurysm volumes who were followed without intervention. The continued development of type II endoleaks beyond the perioperative period supports the need for continued endoleak surveillance.